Gun barrel liner



1 D. R. STERBA ET AL 3,972,800

GUN BARREL LINER Filed March 26, 1956 GUN BARREL LINER Donald R. Sterba, Westchester, and Arthur M. Olsen, Chicago, Ill., assignors to Crane Co., Chicago, 111., a corporation of Illinois Filed Mar. 26, 1956, Ser. No. 574,046

2 Claims. (Cl. 29-11) This invention relates to improvements in a gun barrel or the like, and, more particularly, it is concerned with a novel form of liner therefor.

One of the more important objects 'of this invention is to provide for a gun barrel liner in which a plurality of washers arranged in abutting relation are pre-formed in an assembly and whereby the said washers will remain uniformlylspaced despite their exposure to the high temperatures associated with gunfire.

In order to appreciate the problem heretofore encountered in connection with gun liners, it should be understood at the outset that previous test results have indicated that transverse segmented liners tend to ratchet or to move forward as the barrel becomes heated and as the interference or frictional contact between the liner and the barrel recess is reduced during the course of fire.

Therefore, it is one of the more important objects of this invention to provide for a structure of assembled washers in which longitudinally extending keys or strips are welded or otherwise fusibly attached to the washers and which also permit of the washers being inserted into the gun barrel as an integral unit.

Heretofore, it has been difiicult, if not impossible, to accomplish the above results.

Another important object is to provide for a liner assembly of washer-type construction in which manufacturing costs are substantially reduced over those structures previously provided.

Other objects and advantages will become more readily apparent upon proceeding with the specification read in light of the accompanying drawings, in which:

Fig. 1 is a fragmentary sectional assembly view of a gun barrel and liner assembly embodying our invention.

Fig. 2 is a magnified view of the novel liner assembly.

Fig. 3 is an end elevation of the washers used in the liner assembly.

Fig. 4 is a magnified fragmentary sectional view of the washer and liner assembly.

Fig. 5 is a fragmentary sectional view taken on the line 5-5 of Fig. 4.

Similar reference numerals refer to similar parts throughout the several views.

Referring now to Fig. 1, a gun barrel generally designated 1 is shown having at its breech end or left-hand end a suitable retainer member or bushing 3 threadedly attached to the barrel as at 4 and apertured as at 5 with the usual open end or receiving portion 6. The latter portion may be suitably formed in a variety of ways as determined by the type of service for which the gun barrel is to be used. At its opposite end portion, the recess 7 of the gun barrel is preferably provided with a shoulder as at 8 whereby to receive and support the washers in abutting relation under the urge of the said retainer member.

At the outset, attention is directed to the fact that while a prerifled washer is illustrated and described herein, in most instances it may be preferable to use washers having plain circular interior, that is, unrified, and therefore to follow with the rifling operation after the washers have been assembled and actually before being placed into the barrel. On the other hand, under some conditions it may of course be desirable to provide that the washers are pre-formed as indicated generally at 11 with the required size, pitch and location of the contiguous rifling portion in each of the washers before their assembly to form the liner, but the latter method is a secondary or alternative one rather than primary or preferred. In such cases in which the washers are relatively so arranged rotatively and pre-rified before assembly the rifling as stated is complementary to the rifled portions in each adjoining washer. At the opposite end portion of the barrel, it should also be understood that certain of the washers at the said breech end after their assembly to form the liner as illustrated may be suitably machined or otherwise formed to provide the chamber 10.

At its opposite end portion, it will be noted the threaded retainer 3 is provided with an end transversely extending surface 12 bearing in abutting relation against the transverse surface of the last washer, as shown, thereby to hold the assembly of the plurality of washers firmly in place against the shoulder at the opposite end of the barrel 1. It will be appreciated that before such insertion of the said washers in assembled relation within the barrel takes place, the said assembly of washers forming the liner, as shown more clearly in Fig. 2, are machined preferably by a milling cutter moving transversely of the assembled washers thereby to provide the longitudinally extending spaced-apart grooves 14 on the periphery of the assembled washers for receiving the alignment strips or keys 15 as shown more clearly in Fig. 4. Preferably, the said strips are weldedly attached to each of the washers by means of the spot welds 16, as illustrated. It will be clear that these strips not only prevent the washers from relative rotation, but also serve to hold the washers from moving forward as the barrel becomes heated and as the frictional surface restraint or interference between the periphery of the washers 9 and the bore 7 of the barrel is reduced during the course of gunfire.

It will, of course, be understood that in such cases as the alternative arrangement above referred to wherein the washers are provided with the grooves 11 and the lands 13 to form the said rifling, the connections between such grooves and lands with each immediately adjoining washer are substantially contiguous and therefore without any objectionable interruptions or breaks between each washer.

In eifecting the assembly of the plurality of washers to form the liner, it will be appreciated that, as hereinabove referred to, the grooves 14 are so arranged and spaced peripherally relative'to the lands and grooves 13 and 11 respectively forming the said liner rifling so that when the individual tack welding at 16 on each washer and strip is subsequently completed a substantially integral liner is the result, while at the same time possessing desirable flexibility and durability in guarding against undesirable rotation and ratcheting in the course of service of each of the washers relative to each other and to the liner assembly per se.

The assembly hereinabove described is of course susceptible of many forms and applications. Therefore, it will be appreciated that while only a single embodiment of the liner assembly has been shown and described, the actual form of such washers and arrangement of the respective rifling used may vary quite substantially. In addition, the manner in which the longitudinally positioned strips 15 are arranged and mounted may also change from the illustrated form without departing from the principles of assembly set forth and as hereinafter claimed.

the washers and-assembling said washers to hold against relative rotation,- applying strips to predetermined portions of said outer edges,- welding, said peripheral portions of the outer edges ofZwashers to hold the latter against substantial movement; and finally assembling the assembled washers within the barrel.

2. In the methodEof making a gun barrel or the like,

the steps of which comprises the insertion into the barrel of a plurality of washers in abutting face to' face relation to each other, the steps including pre-forming the outer edge surfaces of the washers with perimetrally spaced apart recesses and assembling said washers to hold the Washers against relative rotation, the said latter steps including the application of a longitudinally positioned element substantially transversely across the outer edges of the assembled washers within the said spaced apart recesses, and applying fusibility by heat directed to a location between the said element and the outer edges of the washers to hold each of the washers against relative movement upon assembly with the barrel.

References Cited in-the file of this patent UNITED STATES PATENTS 6,090 Fitzgerald Feb. 6, 1849 43,825 Ames Aug. 16, 1864 47,177 Ame s Apr. 11, 1865 496,395 Brown May 2, 1893 595,464 Blood Dec. 14, 1897 821,331 Blood May 22, 1906 1,167,233 Warner Jan. 4, 1916 1,181,704 Warner May 2, 1916 20 2,609,631 Garand Sept. 9, 1952 

